The present disclosure relates generally to optical interconnects and particularly to a silicon carrier for optical interconnect modules.
Optical interconnects are used in a variety of application to couple optical components to electrical components. It is generally recognized that a preferred approach to this problem involves integration of optical components into multichip modules (MCMs) or single chip modules (SCMs). One existing technique includes directly mounting a laser array onto the silicon germanium (SiGe) laser driver chip. This approach, however, adds extra cost and creates difficult thermal challenges. The thermal challenges are twofold; first, the thermally sensitive laser is in intimate contact with the heat producing SiGe driver circuits which affects both laser performance and reliability. Second, a heat spreader on the driver circuit is made significantly less effective, since the contact area to the driver is small because the heat spreader must not contact the chip in the area of the laser and the driver wirebond pads.
The added cost comes from the SiGe chip, which may be greatly oversized to perform packaging functions as well as contain the necessary driver circuitry. The circuitry is not very efficiently layed out with this design, and is estimated to be less than 15% of the chip area. Thus, there is a well-established need for a new type of laser array package.